Final answer:
The passengers on Flight 93 knew their plane was being hijacked and took heroic actions to prevent further damage.
Step-by-step explanation:
The Passengers on Flight 93 Knew Their Plane Was Being Hijacked
The passengers on board Flight 93 knew their plane was being hijacked because they were able to make phone calls to loved ones and were informed of the other hijackings via these calls. They were aware of the catastrophic events unfolding and realized their plane was also in danger.
The actions of the passengers on Flight 93 were heroic as they decided to take action against the hijackers. They attempted to storm the cockpit and disarm the hijackers, ultimately causing the plane to crash in a field in Pennsylvania.